Activists blocking construction of the controversial Dakota Access Pipeline are preparing their encampments for the arrival of harsh winter weather.

(KUSA) From peaceful protests to chaotic marches – and from a camp of thousands to a street protest of hundreds: The Dakota Access Pipeline stirs strong emotions.

“This is my ancestral land – this is my Ireland, this is my Italy, this is my Africa. This is our land,” Simon Moya-Smith of Denver said, who is Oglala Lakota and one of a number of Coloradans who traveled to North Dakota to join the protest.

For more than seven months, several thousand people have gathered in North Dakota near the remote Standing Rock Sioux Reservation to protest the oil pipeline. The argument is over danger to the water supply and Native American rights.

here are several issues at play here. One is that the pipeline will pass through sacred, historic sites and part of the watershed of the Missouri River, which is the reservation’s source of drinking water. The other argument is that the pipeline is going through land that once belonged to these Native Americans under a treaty from 1851. It’s a treaty that legal experts say, depending on how you look at it, was either “breached” or “renegotiated” several times since then.

On top of that, the original pipeline route had it going much closer to more populated areas closer to Bismarck. However, concerns about potential water contamination there pushed it farther south, closer to the Standing Rock Sioux Reservation.